List supported ranking slugs, or read a supported legacy category.

Omit category for the slug index. The two accepted category aliases return the eastern-small-local-models ranking; use /api/rankings/{slug} for other rankings.

Inputs. Path, query and header fields are listed below. No request body is required.

Outputs. See each status below for its media type, schema and headers. A missing record or unavailable capability is not a successful empty result.

Errors. API JSON failures use the documented response schema. Read code, message and next; retry only when the response allows it. Auth, invalid input and missing records need a caller change.

Rate limits. Public read budgets apply by client IP and route group. This operation can have a smaller route-specific budget. Read Retry-After on 429 or retryable 503 responses.